This invention is directed to an improved method and apparatus for measuring organic carbon in an aqueous solution. More particularly, the present invention is directed to an improved method and apparatus for automatically selectively introducing successive samples of a liquid from at least one pressurized line into an apparatus for measuring the content of organic carbon.
Prior art type carbon analyzers have generally been limited to devices having means for manually introducing single samples of an aqueous solution to be analyzed. A example of such a device is described in U.S. Pat. No. 3,958,941 which is owned by assignee of the present invention. In the apparatus described U.S. Pat. No. 3,958,941, a syringe is used to introduce a sample through a rubber septum. It is also known in the prior art to analyze a plurality of samples disposed in individual test tubes. One such device is called Photochem Autosampler and is produced by Analytical Products of the Sybron Corporation. Both of these methods have the disadvantage of having to be performed, at least to some extent, manually and having the potential of introducing impurities into the system thereby causing false measurements.
There also exists in the prior art metering pumps or sample loops for introducing individual sample quantitites into an organic carbon analyzer. However, these systems have the disadvantage of having relatively high initial cost and maintenance or have relatively low reliability, accuracy and efficiency.
Applicants have invented an improved method and apparatus having relatively low cost, simple structure, accurate in dispensing amounts of sample while minimizing the introduction of any impurities to the measuring system.